Sciencemadness Discussion Board

Reactivity of super cold EtOH

ave369 - 8-7-2015 at 14:03

Hi everyone!

Recently I was wondering about using cryohol (ethanol cooled to dry ice temperature, -79 Celsius) as a solvent. Here's what I want to ask: does low temperature increase ethanol's ability to resist oxidation, so compounds that normally oxidize ethanol can be dissolved in it? It seems to be the case, I've read recomendations to separate KOH from various oxidizers such as permanganates and ferrates with cryohol.

And how exactly does cooling to this temperature affect solubility of various salts in EtOH? Is cryohol notably different as a solvent from ethanol of normal temperature?

[Edited on 8-7-2015 by ave369]

aga - 8-7-2015 at 14:10

It's colder, so less energy, so less stuff happens in the same Time as when it is hotter, with more energy.

Venturing further (in order to expose my ignorance and be corrected) :-

If you can calculate the activation energy for an EtOH oxidation reaction (i can't) then you will have a level of energy required for that reaction to occur (ignoring kinetics for now).

At -79 C the energy available has been reduced, so is there sufficient energy in the system to allow the reaction ?

Intuitively speaking, less energy should result in slower reactions, and solvation is a reaction in the pure sense of the word.